Few had expected Ole Gunnar Solskjaer's side to return from the south coast with a point never mind all three and that result has seen them claw back some of their relegation rivals.

The Bluebirds remain 19th in the standings but have halved the gap to safety to three points as the season enters the final four matches.

"It is huge," midfielder Whittingham said. "It was a must-win for us and to get three points drags a lot of teams into it and gives us a fighting chance.

"I said before it was a must-win. We felt like if we didn't get three points then it would probably leave us a little bit out in the cold.

"But it was a good result for us against a good Southampton team, so to get three points was unbelievable.

"The last 10 minutes they had so much of the ball and putting it in our box, so it was about how we defended.

"The boys defended really well and we're really happy to get three points."

Next up for Cardiff is another must-win clash against Stoke, who head to south Wales buoyed by four wins from their past five matches.

"It is going to take a lot of fight," Whittingham said. "There are no easy wins in the Premier League.

"It would be nice to follow this up with another win on Saturday, back-to-back wins would be huge. It is about how we prepare again this week."

Victory against Mark Hughes' side will be vital to any hopes they have of beating the drop and would be just the fourth in the league during Solskjaer's reign.

Arriving as Malky Mackay's replacement in January, the Norwegian has so far struggled at the Cardiff City Stadium even though his approach has impressed the players.

"He has brought an air of calmness, to be honest," Whittingham added.

"He wants us to play the right way, wants us to play football, but it is how we fight as well.

"We did that and it is a great result for him and, of course, the fans."

In truth, the deciding factor at St Mary's was the grit and determination Cardiff showed after Cala found the net.

Southampton bossed the encounter but they failed to turn their dominance into goals, with manager Mauricio Pochettino bemoaning a lack of cutting edge afterwards.

Saints midfielder Steven Davis echoed those sentiments and vowed to kick on when they travel to face his former club Aston Villa next weekend.

"I think we played generally quite well, moved the ball well and had a lot of possession, created a lot of chances, but we didn't do enough in front of goal before they got the first one," he told Saints Player.

"We'll go away from it feeling disappointed and frustrated because we always look to win our home games and unfortunately we couldn't do that.

"It's just a frustrating day more than anything because of the way that we've played.

"There are positives to take but it didn't drop for us in front of goal and we couldn't get the three points so we have to look forward now to our four remaining games and try to pick up as many points as possible.

"I think in the way we've shown in every game this season, the demands we've placed on each other to drive this club forward, and to try and drive each other on as much as possible, and there's still four games with a lot to play for in our minds, so we need to play and train in that way."